Over the past two decades, computer equipment and associated peripheral equipment have evolved through higher data processing rates into more standardized packaging techniques. System packaging which involves not only interconnections of integrated circuits to printed circuit boards but also printed circuit boards to other printed circuit boards and then to the outside world has evolved into a somewhat standard format. Printed circuit boards can be connected together with either a third printed circuit board (motherboard or backplane) and two connectors or a flexible cable with connectors at each end. The most popular of these connectors is now the post and socket type of connector, a two-piece connector. High reliability and standardized design have contributed to this current popularity. The most common configuration used for the male half of this connector is the 0.025 inch square wire wrap post placed on a 0.100 inch by 0.100 inch grid.
However, high speed digital and analog signal processing systems normally require coaxial grade connections between printed circuit boards or between a printed circuit board and the outside environment. The use of standard radio frequency (RF) type coaxial connectors in this type of packaging system is not desirable or practical because of exposed metal parts which provide opportunity for circuit damaging electrical shorts and because of their size incompatability with the high signal density requirements of the equipment.
Various methods and equipment have been devised to overcome the difficulties outlined above of connecting a printed circuit board with another piece of computer or other electronic equipment by means of coaxial cables. A shielded coaxial ribbon cable assembly which utilized curing inside the assembly curable elastomeric insulation to protect the joined conductive parts was devised by Tighe, Jr. in U.S. Pat. No. 4,596,432. A latching two-part nylon housing system to connect single or twin coaxial cables to a printed circuit board has one housing part secured to the board and the second part, into which the coaxial cables are plugged, latches onto the first part to effect attachment as shown by Smith in U.S. Pat. No. 4,008,941. The device does not use miniaturized standard post and socket hardware, however.
Another way to try to minimize signal distortion in a connector is described by Abraham, et al., in U.S. Pat. No. 3,958,852, by use of a housing with a plurality of coaxial jacks, a ground plane, and two sets of contact springs, all mounted within the housing. Each coaxial jack has a tubular element connected to the ground plane and a socket mounted inside the tubular element. Again, this assembly is not used with standardized miniature post and socket hardware.
A square grid to guide coaxial cable terminals into positive indexing with contact pins extending from a circuit board was provided by Uberbacker in U.S. Pat. No. 3,587,028. The grid structure also served as a common ground for the sheilds of the cables. Another connector utilizable for coaxial cables to connect to them to a row of spaced posts was shown in U.S. Pat. No. 3,569,900. This connector has common grounding for the coaxial shielding at the rear of the connector and does not show provision of shielding in the area of contact between the signal conductor of a coaxial cable and a pin.